Not applicable.
Not applicable.
Not applicable.
The present invention relates generally to a spray gun more particularly to a compression structure of the spray gun.
As shown in FIGS. 1 and 2, a spray gun of the prior art comprise a main body 10 which is provided in the interior with a guide tube 11, an upright tube 12, and a compression tube 13. The guide tube 11 is connected at the front end with a discharge tube 14 which is connected with a spray head 15. The guide tube 11 is in communication with the upright tube 12 via a through hole 16. Located between the front end of the interior of the guide tube 11 and the discharge tube 14 is a stop pin 18, which is urged by a C-shaped elastic piece 17. The compression tube 13 is provided at the inner end with a through hole 29 in communication with the upright tube 12. A piston 30 is received in the outer end of the compression tube 13 in conjunction with a metal spring 31. A trigger lever 32 is fastened pivotally with the main body 10 such that the trigger lever 32 is contiguous to the spray head 15, and that the trigger lever 32 presses against a rod portion 33 of the piston 30. As the trigger lever 32 is activated to actuate the piston 30, the pressure is built up in the compression tube 13. As a result, the spray head 15 disperses the contents of a container in the form of a spray by the air pressure in the compression tube 13 which serves as a compressor.
With the exception of the metal spring 31, all component parts of the prior art spray gun are made of a plastic material, which is recyclable. It is time-consuming to remove the metal spring 31 from a discarded spray gun in the recycling process. In addition, the prior art spray gun is defective in design in that the rod portion 33 of the piston 30 is apt to sway at the time when it is pressed against by the trigger lever 32, thereby resulting in poor performance of the spray gun.
The primary objective of the present invention is to provide a spray gun with a compression structure devoid of a metal spring, so as to facilitate the recycling of the spray gun.
In keeping with the principle of the present invention, the foregoing objective of the present invention is attained by the compression structure comprising a compression tube which is in communication with an upright tube which is in turn in communication with a guide tube. The guide tube is in communication with a spray head. The compression tube is provided with an elastic tube fitted thereinto. The elastic tube has a closed outer end. A connection rod is connected at an inner end with the outer end of the elastic tube such that an outer end of the connection rod is pivoted with a trigger lever. The elastic tube serves as a piston, which is actuated by the trigger lever via the connection rod to compress fluid, thereby enabling the spray head to disperse the contents of a container in the form of a spray by the fluid pressure.